Two-cycle internal-combustion engine.



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BUSTI -M. PERRERO & A. TWO CY OLE INTERNAL 00M APPLIQU ATION FILED DBO.16

PATENTED AUG. 29, 1905. v, M. PERRERO & A. PRANCHETTI. TWO GYOLB'INTERNAL COMBUSTION ENGINE APPLICATION FILED B30 16, 1902.

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MICHELE FERRERO, OF TURIN, AND ALESSANDRO FRANCHETTI, OF FLORENCE, ITALY.

TWO-CYCLE iNTERNAL-GOMBUSTION ENGBNE.

Specification of Letters E atent.

Patented Aug. 29, 1905.

Application filed December 16,1902. Serial No. 135,384..

To all whom it may concern:

Be it known that we, MIonnLn FnRRnRo, mechanical engineer, of 12 Col-so Ducadi (Jrenova, Turin, and ALnssANnao FRANCHE'ITI, mechanical engineer, of 29 Viale Principe Eugenio, Florence, Italy, subjects of the King of Italy, have invented certain new and useful Improvements in Two-Cycle Internal- Combustion Engines; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

Our invention refers to two-cycleinternalcombustion engines in which all inlet-valves are dispensed with.

An engine constructed according to our invention has three or more motor cylinders, each of which has an enlargement on its rear side. The small-diameter front parts of the cylinders are the motor-cylinders proper and have their inlet and exhaust ports open, as

' usual, when the piston reaches the end of its stroke. The enlargements of the cylinders, wherein the large pistons slide, act as air or explosive-mixture pumps, according to the engine being or not provided with a separate fuel-inletdevice. of the pumps may consist either in the annular space between the large piston and the enlarged part of the cylinder or in the correspondingcrank-box. If the pumps only suck in air, the engine must be fitted with separate contrivances for feeding the fuel, which may be similar to those already known. The number of cylinders is so chosen and the motions of the pistons are so timed that each piston acts asan admission or suction valve for feeding the pump of the adjacent cylinder, while the first piston feeds the pump-of the last cylinder. All of this. .will be better understood with the aid of the accompanying drawings, which show, by way of example, three different forms in which our invention may be carried out.

Figure 1 is a longitudinal section of one of said forms ofexecution; Fig. 2, a cross-section of another form. Fig. 3 is a longitudinal section of another form. Fig. 4 isatransverse section of the form shown in Fig. 3.

All of the figures show a three-cylinder engine whose pistons are connected with cranks grees.

The compressioi'1-cl1am bers In all figures, 1: represents combustionchambers. If the engine be fitted with separate contrivances for feeding the fuel, this latter (gas, oil) is compressed into the combustion-chambers k for instance, by appropriate pumps. (Not shown in the drawings.)

represents admission-ports cut at the bottom of each motorcylinder and connected, by means of conducts f, with one of the pumps formed by the enlargements of the cylinders.

8 represents exhaust-passages cut at the bottom of each motor-cylinder.

According to Figs. 1 and 2 the compression-chambers of the pumps consistin the annular space 0 between the large piston and the enlarged part of the cylinder. Pump 1 feeds cylinder 2, while pump Qfeeds cylinder 3 and pump 3 feeds cylinder 1 through the admission-ports vi. According to Fig. 1 the air or the explosive mixture, as the case may be, is admitted to the pumps through the ports 0, which are uncovered at the proper time by the lower edge of the enlarged part of the piston, the crank-box communicating with the atmosphere or with a receptacle containing the explosive mixture through the ports Theoperation of the modification illustrated in Fig. 2 of the drawings is the same as that described in connection with Fig. 1, except that while in Fig. 1 the air or explosive mixture is taken from the port 0 into the crankcase, the port being connected to the upper portal by the passagefin Fig. 2, the same port 2' is used both to admit the air or explosive pump or crank case 1. This is accomplished by providing the piston with a valve-opening d, which when the piston is at. the upper end of its travel puts the port 2 in communication with the pump 1, which feeds the cylinder 2. In both cases piston 2 acts as distributingvalve for pump 1, piston 3 for pump 2, and piston 1 for pump 3. It is to be understood that said ports may be differently shaped and uncovered by the pistons in any convenient manner, if only this takes place at the proper time. In the'position shown by thevdrawings piston 1 is covering the admission-port sion-stroke and feeding the same cylinder namely, cylinder 1through the passage f, connecting 3 with 1, and through theports Piston 2 is on the point of performing its I downwardstroke and covering the admissione mixture into the cylinder 1 and also into the of pump 3, which is performing its compresport of pump 1, which in its turn is on the point of beginning compression. Piston 3 has uncovered the admission-port of pump 2, which is drawing in air or explosive mixture. At the same time the exhaust of the combustion-gases is going on in the motor-cylinder 1 while the same is being fed with air or explosive mixture. The working stroke is meanwhile being performed in cylinder 2 and compression taking place in cylinder 3. These phases are going on in the same succession in each of the three cylinders, while the crank.- shaft is revolving in the direction shown by the arrow.

According to the arrangement shown in Figs. 3 and 4 the compression-chamber of the pumps is contained between the enlarged parts of the pistons and thecrank-boxcs, which are separated from each other in an air-tight manner, while the space 0 communicates with the atmosphere or a receptacle of explosive mixture through the ports '1'. Each pump feeds the motor-cylinder situated on the same axis through the ports a. The admission to the pumps takes place through the ports w, which are uncovered by the upper edge of the enlarged part of the pistons, while the latter approach their lower dead-points. The air o explosive mixture, which may then enter through the ports '2', the annular space 0, is sucked from said annular space into the pump, communicating therewith through the corresponding ports 0. In the position shown by the drawings the motor-cylinder 1 is rcceiving air or explosive mixture compressed by pump 1, while the passages s allow the combustion-gases to escape therefrom. The working stroke, as well as the compression of the air in the crank-box, is meanwhile taking place in cylinder 3. The pump of cylinder 2 is at the same time sucking air or explosive mixl l i 1 l l l 1 ture through 7' and 0, which have been uncovered by piston 1 while the charge is being compressed within the motor-cylinder 2. The different phases succeed each other just as in the examples shown in Figs. 1 and 2, while the crank-shaft is turning in the direction shownby the arrow.

It is to be u ndcrstood that the cylinders may be more than three'in number and may have 5 their axes either parallel and situated in the same plane or inclined to each other and situated in one or more planes parallel to the crank shaft or shafts, provided each cylinder be fed by one of the pumps and a pump he f fed in its turn at the same time or not through ports which are being uncovered by one of the pistons.

\Vhat we claim as our invention is v 1. An internal-comlmst-ion engine having three or more cylinders acting both as motorcylinders and feed-pumps, each of said pumps except the last one feeding one of the adjacent motor-cylinders and the last pump feeding the lirst motor-cylinder, the piston of said 5 lirst motor-cylinder acting as a distributingvalve for the pump of said last cylinder.

2. An internal-combustion engine having three or more cylinders, acting both as motor-cylinders and feed-pumps, in which each '7 piston has an enlargement, the enlarged part of each piston acting as an admission-valve for the pump feeding the motor-cylinder, wherein the thinner part of the same piston slides. I 7

In witness whereof we have hereunto set our hands in presence of two witnesses. V

MICHELE FERRERO. i ALESSANDRO FRANCHET'IL' Witnesses:

' CLEMENTE GIUTZETTI, ,GUIsErPE OTTOLA. 

